The invention pertains to seats, and particularly relates to seats of the type employing a sheet metal contoured pan upon which a resilient foam cushion is assembled. Such seats are commonly employed on industrial equipment, tractors, riding lawnmowers and the like.
In the past, seats of the above type are fabricated by supporting a foam cushion upon a sheet metal seat pan wherein the cushion lower surface closely conforms to the pan, and a retainer is utilized at the pan and cushion peripheries to mechanically assemble the cushion to the pan. The retainer is usually in the form of a pinch rim or bead of a U cross sectional configuration which receives the cushion cover and pan and mechanically holds these components in contiguous relationship. This mode of assembly is troublesome and expensive, and during use the retainer may work loose of the pan causing disassembly of the seat components.
It is known to mold resilient cushions to a seat pan or support, and it is also known to extend the foam about the edge of the pan. For instance, U.S. Pat. Nos. 2,893,476; 3,669,498; 3,833,260 and 4,103,966 disclose seat constructions wherein the cushion extends adjacent, and partially about, the pan periphery, but these seat constructions are of a molded type, and the cushion is not separately assembled to the pan.
It is an object of the invention to provide a seat assembly utilizing a metal pan and a resilient foam cushion wherein the cushion is mechanically connected to the pan without requiring separate retainer or assembly structure.
Yet another object of the invention is to provide a seat assembly utilizing a pan and a foam cushion wherein the cushion is self-connecting to the pan, and the seat assembly basically consists of only the pan and cushion, eliminating additional retainer assembly components.
Another object of the invention is to provide a seat assembly employing a pan and flexible foam cushion wherein the cushion is of such configuration adjacent its periphery that the cushion "snaps on" the pan, and the cushion configuration includes a hook and lip configuration to produce the desired self-attachment function.
Another object of the invention is to provide a resilient synthetic foam cushion of such configuration that the cushion is self-attachable to a seat pan by a "snap-on" connection.
In the practice of the invention a contoured sheet metal pan includes a peripheral edge, and a synthetic foam cushion rests upon the upper surface of the pan to provide the seating surface. The cushion usually includes a cover, such as of vinyl.
The cushion is provided with a peripheral region of foam which is shaped to extend about the pan periphery, and this cushion peripheral region is formed with a hook and lip configuration wherein the lip extends "inwardly" toward the pan and is so shaped as to closely embrace the pan peripheral edge. In this manner the cushion is "snapped on" the pan, and the cushion is maintained in its assembled relationship to the pan solely by the hook and lip shape of the cushion periphery itself.
The peripheral region of the cushion is such that sufficient foam material exists at the hook and lip region to impart to the cushion peripheral region the necessary strength and resistance to deformation to permit the cushion to achieve a firm mechanical relationship to the pan. During assembly the cushion is stretched to distribute the cushion over the pan and permit the lip to be pushed over the pan edge, and the natural resiliency of the cushion material causes the cushion to closely conform to the upper surface and periphery of the pan.